Abstract
Vehicle cabin air contains various chemical substances from interior materials, personal belongings, and combustion gases, raising concerns about potential health risks. Conventional target analyses are limited to specific compounds and are insufficient for comprehensive risk assessment. In this study, we developed a risk screening approach by combining quantitative non-targeted analysis (qNTA)—which integrates thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) with post-column reaction-flame ionization detection (PR-FID)—with in silico toxicity prediction. This method enables simultaneous qualitative and quantitative evaluation without standard analytical reagents by integrating structural information from MS with methane-equivalent concentrations obtained via FID, and can be applied to unknown substances. Using the proposed approach, approximately 130 chemical substances were identified and quantified in the cabin air of trucks, with Hexane (track A: 550* μg m−3, track B: 710 μg m−3) (* indicates reference values) and Ethyl acetate (track A: 560* μg m−3, track B: 44 μg m−3) detected at relatively high concentrations. Furthermore, risk potentials (MOEp) were calculated based on predicted no-observed-effect levels (NOELp) from in silico toxicity prediction and estimated human exposure rates. As a result, Hexane (MOEp = track A: 490, track B: 370) and Butylcyclohexane (MOEp = track A: 2,700, track B: 1,900) were identified as compounds with high-risk potential.
